<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><br class=""><div><blockquote type="cite" class=""><div class="">On Jun 1, 2015, at 1:34 PM, Phillip Hallam-Baker <<a href="mailto:phill@hallambaker.com" class="">phill@hallambaker.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div dir="ltr" class=""><br class=""><div class="gmail_extra"><br class=""><div class="gmail_quote">On Mon, Jun 1, 2015 at 10:27 AM, Arnold Reinhold <span dir="ltr" class=""><<a href="mailto:agr@me.com" target="_blank" class="">agr@me.com</a>></span> wrote:<br class=""><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">A small suggestion: instead of slavishly following RFC4648 Base-32 format, I would suggest a modified Base-32 where the letters I, O, and L are excluded from the encoding alphabet as they are too easily confused with the digits 0 and 1 (L being confusing in lower case). Maybe exclude S as well for potential confusion with 5. Only 32 of the possible 36 characters are needed, so excluding three or four characters poses no technical problem. Here is a worst-case example I concocted: 0lSS0-l1151-I5S1O-I05S1 Of course the potential for confusion is font dependent but I don’t think it is practical to specify fonts in such a standard.<br class="">
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Since the fingerprint strings are intended for human recognition, we should do everything possible to minimize confusion. At the standards writing stage, this is a cheap improvement.<br class=""></blockquote><div class=""><br class=""></div><div class="">Base32 does the same thing by excluding the corresponding numbers. Of course, both could be less confusing. The coding was originally proposed by Phil Zimmerman.</div><div class=""><br class=""></div><div class="">Maybe an explanatory note… </div></div></div></div>
</div></blockquote><br class=""></div><div>I should have read the RFC more carefully. There is a second "Base 32 Encoding with Extended Hex Alphabet” that confused me (section 7). “Base-32 Encoding” (section 6) as you say discards the digits 0 and 1, but not 5. Close enough. </div><div><br class=""></div><div>It’s good to know that they and you got it right the first time.</div><div><br class=""></div><div>Arnold Reinhold</div><br class=""></body></html>